Final Boss
by Sydella
Summary: After all the enemies he has defeated, the greatest enemy Tsuna has to face is...himself.


Not long after Reborn announced his plans to make Tsuna the Neo Vongola Primo, those closest to Tsuna began to notice changes in the boy. It all started when Tsuna's smile no longer seemed genuine and became a cold, humourless thing that frightened everyone around him. Innocence vanished from his eyes and was replaced with a permanent look of displeasure. However, no one could say that he was doing badly in any area of his life. He was now passing all his classes, he could hold his own in a match against his Arcobaleno tutors, and his relationship with his father had improved considerably. So what had gone wrong?

"Maybe we should ask him," Yamamoto suggested. The tenth-generation Guardians were holding an impromptu meeting in a small, airless storeroom. The baseball player's skin prickled uncomfortably in the heat, but his physical unease was nothing compared to the emotional turmoil churning within him.

"I did ask the Tenth." Gokudera's misery was evident. "He just looked at me and said he's fine."

"He is clearly _not_ fine," Hibari said firmly. It was a testament to the severity of the situation that Tsuna's Cloud, of all people, was actively joining in this discussion. "We must get to the bottom of this-"

The door to the storeroom flew open, interrupting Hibari mid-sentence. Tsuna stood in the doorway, smiling that strange cold smile. The young heir looked around at them and intoned: "So this is where you've been. I've been searching all over for you guys."

Silence ensued. The Guardians stared at their Sky, who just kept smiling as if nothing was wrong. But something was clearly very wrong, and although Tsuna was only standing a few feet away from them, they had never felt more distant from him. There might as well have been oceans separating their Sky from his Elements.

"Tenth," Gokudera said tentatively. "Are…are you feeling all right?"

Tsuna's smile widened, and Gokudera involuntarily shuddered. "Never better, Hayato."

Hibari abruptly stood, drawing all eyes to him. "Small animal, I'll bite you to death."

"Oh? I thought we'd reached an agreement, Hibari-san." The dreadful smile didn't leave Tsuna's face. "Don't make me sad. Aren't we friends?"

"No. You've changed."

"Have I?" Tsuna pouted. "Oh well, I can manage without you. I can manage without _any_ of you." Without another word, he turned and walked away, leaving his Guardians to stare after him.

"Well, that was productive," Mukuro muttered.

"What do we do now?" Chrome asked anxiously.

Ryohei gnawed on a thumbnail, a nervous habit Kyoko had been trying to cure for ages. "Let's wait and see what Sawada does next."

X

A few days later, some third-year bullies tried to beat Tsuna up, as per their usual routine. This time, Tsuna retaliated with the force of an enraged animal. Minutes later, the bullies lay in a heap on the ground, faces swollen and bleeding profusely.

Hibari was patrolling the school grounds and chanced upon them. "Who did this to you?" he asked, feeling torn between sadistic pleasure and resentment towards whomever had stolen his prey.

"I did," Tsuna said pleasantly.

Hibari stared at him in disbelief. "You?"

"That's right."

Hibari let out a mocking laugh. "You're lying."

"No, Hibari-san." Tsuna held a smelly, sneaker-clad foot up to the nearest bully's face; the bully took one whiff of it and promptly fainted.

"Wao." Hibari glanced at the hapless bullies and couldn't help but smile. "Not bad, small animal." The prefect looked up and, to his astonishment, found that Tsuna had suddenly vanished.

 _Where'd he go? He was standing right here…_

"Hibari-san!" Tsuna's voice rang out. The smaller boy was now standing at the other end of the school courtyard. Hibari blinked. How had Tsuna been able to move so quickly?

"I'm going home." And with that, Tsuna turned and walked away again.

Hibari frowned. He didn't like this at all.

X

Later that day, Tsuna was summoned to Timoteo's office.

"We meet again, Tsunayoshi-kun," Timoteo greeted him warmly. The two Vongola bosses courteously shook hands and sat down.

"May I know why you have requested my presence on this pleasant evening?" Tsuna's tone was gentle. Perhaps a little too gentle. The ninth-generation Guardians fidgeted and exchanged worried glances.

Timoteo watched his young successor. "I've been hearing some very interesting things about you."

"Oh?" Tsuna's smile was, if anything, even more malicious than before. "Good things, I hope."

"I'm afraid not, Tsunayoshi-kun." Timoteo's gaze was unwavering. "Reborn tells me that you've been frightening your ladies. Your Guardians are now uneasy around you as well."

Tsuna pursed his lips. "Haru-chan and Kyoko-chan have given no indication of doubting my intentions."

"Yes, Tsunayoshi-kun. Because they're _afraid_." Timoteo took great care to emphasise the last word. "Naturally, they would not want to provoke you."

"Provoke?" Tsuna shifted slightly in his seat. "My girls know that I'm always willing to hear them out. I do take their concerns very seriously."

"Do you, Tsunayoshi-kun." Timoteo said evenly. It was not a question.

Seconds ticked past. Timoteo's office was air-conditioned, but the temperature inexplicably rose. Beads of sweat rolled down the sides of the old men's faces. And still Tsuna sat stiffly, that horrible smile plastered on his face.

The silence was broken when Reborn entered the office. "Ciaossu." Without preamble, the Arcobaleno leapt up and kicked Tsuna squarely on the chin.

"Now, now, Reborn." Alarmed, Timoteo beckoned his longtime friend and employee to come to his side. "That is hardly necessary."

"You are too kind to No-Good Tsuna, Ninth," Reborn replied, but grudgingly obeyed.

Tsuna was as silent and still as a statue. The corners of his lips turned downwards.

"Tsuna?" Timoteo said gently, leaning forwards in an attempt to decipher the boy's expression.

"DIE!" Tsuna screamed. His eyes suddenly filled with rage, and a torrent of Sky Flames erupted from his bare hands. Before anyone could stop him, the entire office was ablaze. Tsuna ran towards a window and forcibly prised it open.

"Someone stop him!" Timoteo shouted, coughing. "I-I can't see anything!"

"Ninth, please use your Zero Point Breakthrough technique!" Reborn called out desperately. The Arcobaleno pulled out his gun and aimed it at Tsuna. "I don't know what's gotten into you, Tsuna, but how dare you defy me."

Tsuna perched on the windowsill. "Oh, I think you'll find that I'm capable of much more than mere defiance, Arcobaleno of the Sun." The boy paused and crouched, gathering momentum, then launched himself out into the night.

The Flames were extinguished by Timoteo's ice. The men stared at each other, breathing heavily. "This is awful. I can't believe it," Ganauche III, Timoteo's Lightning, wheezed.

Timoteo slowly sat up, clutching his chest.

"The Corruption has begun in our Decimo's heart," the old don said grimly. "We have our work cut out for us."

X

On a beach several kilometres away, an exhausted Tsuna collapsed and lay on the sand for a while, staring at the stars in the endless sky. Presently he stood, brushed grains of sand off his slacks, and walked to the water's edge. Natsu growled softly at nothing in particular. Tsuna stroked the cub's fur, watching the rise and fall of his pet's chest.

"No one understands me, Natsu," he whispered. "Only you know what I'm going through."

He sank to his knees, the cool ocean water lapping at the fabric of his slacks, and cried.


End file.
